Crepe thread and method of making same



Patented Dec. 9, 1941 2,265,202 CREPE THREAD AND METHOD OF MAKING SAME George Schneider, Montclair, N. 1., and William Whitehead, Rye, N. Y., assignors to Celanese Corporation of America, a corporation of Delaware No Drawing. Application February 21, 1939, Serial No. 257,660

11 Claims. (Cl. 57-140) This invention relates to the manufacture of crepe threads of organic derivatives of cellulose and to. the production therefrom of fabrics exhibiting crepe effects.-

An object of. this invention is the economic and expeditious production of crepe yarns or threads containing organic derivatives of cellulose and which are suitable for the production ofcrepe fabrics.

A further object of this invention is the production of crepe-yarns or threads which shrink and buckle with a lower degree of twist, or in shorter periods of time, or at lower temperatures when treated in a creping bath.

Other objects of this invention will appear from the following detailed description and the appended claims.

It has been previously found that if yarns of cellulose acetate or other organic derivative of' or hot water, they produce crepe effects in fabrics containing them when given treatment in hot scouring baths.

We have foun that if filaments, yarns or threads of organic derivative of cellulose have incorporated therein a crepe promoting agent, comprising a substance having a delayed solubility in water, prior to their being twisted in the presence of hot aqueous media, such as steam or hot water, many advantageous results are obtained; Thus, cellulose acetate yarn treated with our crepe promoting agent and then twisted in the presence of hot aqueous media produces at least as good crepe effects as cellulose acetate yarn that has not been treated with our agent prior to the twisting in presence of the aqueous media when (1) it contains less twist, say -15 turns per inch less, (2) fabric containing it is treated in a creping bath of to 0. lower (80 to,

85 C. as against boiling temperature), whereby delustering of the fabric may be avoided, (3) the time of treatment in the boil-off bath is reduced considerably, say to 10 to 20%.

In carrying this invention into effect, filaments, yarns or threadsof any organic derivative of celthe new crepe threads, for example, filaments, yarns or threads containing cellulose esters such as cellulose acetate, cellulose butyrate and cellulose propion'ate, and cellulose ethers such as ethyl cellulose and benzyl cellulose. The invenlulose may be employed in the manufacture of r tion, however, is of especial value and will be described more particularly in connection with the is described in U. S. Patents N such as egg albumen,

production of crepe yarns or threads of cellulose acetate.

As stated above, the crepe promoting agent that is incorporated with or applied to the filaments or yarns in accordance with this invention comprises a substance that has delayed solubility in water, by which is meant a substance of colloidal nature which is not freely soluble in water, but which when treated with water, especially at the temperature of the creping,bath, absorbs water and swells; Examples of the crepe promoting agents that. may be employed in this invention are proteins, whether of animal or vegetable origin such as proteins obtained from soya beans, gelatin or modified gelatin, or other albumens casein, and sericin; proteins which have been. treated with formaldehyde or other aldehydes; gums, such as gum tragacanth; starches; methyl cellulose that swells in hot water; alkali soluble cellulose ethers such as ethyl cellulose and hydroxy ethyl cellulose.

In carrying out this invention any'appropriate means may be employed for applying the crepe promoting agent to the filaments, yams or threads. For example, the crepe promoting agent may be added to the spinning solution or dope from which the filaments constituting the yarns or threads are formed. We prefer, how'- ever, to apply the crepe promoting agent tothe filaments, yarns or threads while they are travelling by passing themin contact with rollers, rods,

pads or other devices supplied or impregnated the materials in the form of hanks in a bath containing the crepepromoting agent. In our preferred form of applying the agent to the materials, it is applied thereto in the form of an emulsion in water with or without an emulsifying agent su ch as a sulphated higher fatty alcohol or a salt thereof. Y

The emulsion employed in accordance with this invention contains such concentration of the crepe promoting agent as to impart thereto a consistency that is convenient. The amount of this emulsion to be applied to the filaments, yarns or threads of cellulose acetateis such that from 1 to 10% of the crepe promoting agent, based on the weight of the cellulose acetate, is retained thereon, depending upon the nature of the agent employed.

As stated above, the filaments, yarns or threads coated or impregnated with the crepe promoting 2,089,191; This twisting may be effected on a device of the kind in which the thread is drawn off over the head of a rotating package through a guide fixed substantially in line with the axis of rotation of the package and is thereafter wound on a bobbin or the like, the thread being passed through hot aqueous fluid on its way from the guide to the bobbin. In this way the yarn is subjected to the action of the hot aqueous fluid during the actual application of twist. The

twisting spindle, the guide fixed in line with the axis of the spindle and the device for applying the hot aqueous fluid tothe filaments, yarns or threads should be so arranged that the twist resulting from the rotation of the package is at least partially inserted while the thread is in contwisting devices, being provided with inlet andv outlet holes for the thread of each twisting device. Such an apparatus may conveniently consist of a horizontal pipe mounted over a row of twisting devices and provided with eyes of porcelain, stainless steel, or other suitable material at appropriate points on top and bottom for the entrance and exit of the threads. The diameter of the pipe should be such as to afford the thread the requisite length of travel in the steam. Al-

ternatively, a pipe having a smaller diameter may be used, in which case the pipe may be provided with hollow nipples communicating therewith and through which the yarn passes, the nipples being of sufficient length to provide, together with the diameter of the pipe, the requisite length of travel in the steam. 1

The presence of the desired moisture may be assured by supplying wet steam to the steaming device and/or by arranging for the condensation of steam to supply the requisite amount of moisture. For instance, small traps for condensed water may be provided at suitable intervals in the steaming chamber and steam injected therethrough by means of small pipes or orifices. Another method of insuring the presence of moisture is to wet the thread with water. For example, the bobbins of thread may be wetted before the twisting operation or, better, water may be applied to the thread by means of a wick or other device after the thread leaves the spindle and prior to its entering the steaming device.

Steam at slightly above atmospheric pressure, or at a pressure of 1 to 2 centimeters of water, is most conveniently employed. If desired, however, the steaming may be effected with steam at any .desired super-'atmospheric pressures, e. g. steam at 10 to 25 lbs. per square inch.

A steam treatment of relatively short duration, such as may be secured by causing the yarn to pass through steam in a path of about 1 to 6 .inches at a speed of from 2'to 10 meters per minute has been found to give satisfactory results. Longer treatments may, however, be employed. For example, the yarn may 'be passed at the said speeds through 6 inches to 12 inches or more of steam.

The-treatment of the thread with hot water- I stage.

thread off from a twisting spindle'and passing it upwardly through a small hole in a suitable receptacle containing hot water, the thread then passing-to a. winding device. The hole may be, for example, about of an inch in diameter and may be provided with means adapted to lead away and pre ,ent from reaching the twisting spindle any liq d issuing from the hole. If desired, the hole may take the form of a short tube of fine bore, fixed in the receptacle, whereby the flow of liquid from the receptacle at the point of entrance of the thread may be reduced.

The duration of the treatment with hot water may be relatively short, such as may be secured when the thread is travelling at a speed of 2 to 10 meters per minute and is in contact with hot water for 1 to 3 inches of its travel. More pro-- longed treatments may, however, be employed.

Very good results may be obtained by using hot water at temperatures of to 100 C. Preferably the watershould be as hot as possible and temperatures of, for instance, to C. are to be recommended. If desired, the hot water may be employed under pressure, for example 2 to 10 or 15 pounds or more per square inch. The use of pressure enables the water to be employed at higher temperatures than is possible under atmospheric pressure. By using pressure, therefore, the temperature of the water may be above 100 C. and to the boiling point thereof at the pressure employed. Water may be employed under pressure, however, when the temperature is below 100 C.

The crepe twisting may be applied in a single If desired, however, the crepe twist may be applied in two or'more stages, at least the final stage of twisting being effected while treating the thread with hot aqueous fluid, as described in U. S. Patent No. 2,088,587.

When the crepe twist is applied in two or more stages the advantages of the process may be obtained when not only the final stage of the crepe twisting but the earlier stage or stages of twisting are also effected while treating the thread with hot aqueous fluid. In fact, it is of great advantage to effect, while treating the thread with hot aqueous fluid, any application of twist beyond the point at which twisting would result in weakening of the thread if the said twisting were eifected without the hot aqueous fluid treatment.

The total twist applied in accordance with the process of the present invention may vary within wide limits, and the crepe figure in the fabric may be regulated according to requirements. The total twist desirable in any particular case dependsupon a number of factors, including the precise eifects required, the number of filaments, and the denier of the thread.

'An important advantage of our process is that good crepeefiects may be obtained with cellulose acetate yarn of lower degree of twist than has beenattainable heretofore. Thus cellulose acetate yarn made in accordance with our invention having as low as 55 turns per inch can produce good crepe effects. The number of turns to be employed may be from 55 to 90 turns per inch, depending on the efiects desired, the greater the number of turns, the less temperature and/or time of treatment being required in the creping bath.

While the process of this invention enables production of threads which yield satisfactory crepe effects without a special treatment, other during twisting may be eflected bydrawing the 75 than the twisting and hot aqueous fiuid treatment characteristic of the process, other treatments may, if desired, be employed further to improve the properties of the crepe threads and/or fabrics produced therefrom. Thus enhanced crepe effects may be obtained by treating the fabrics containing the crepe threads with aqueous solutions of saponifying agents such as the hydroxide or carbonates of sodium potassium or ammonium to superficially saponify the cellulose acetate yarns, prior to treatment with the creping bath. A convenient and effective method of doing this is to pad the fabric with an aqueous solution of an alkaline material, say a solution containing to 40 grams per liter of sodium hydroxide and then drying the fabrics on heated cans.

The highly twisted crepe threads may be incorporated in the fabrics in various ways, for example, the weft alone may be wholly or partially composed of such threads or the warp may also contain them. Valuable fabrics may be produced by employing warp'threads of relatively low twist and in the weft both crepe threads having a left-hand twist and crepe threads having a righthand twist, pairs of threads of left-hand twist alternating with pairs of threads of right-hand twist.

If desired, the cellulose acetate crepe threads may be associated in the fabrics with highly twisted crepe threads of other materials, e. g.'0f natural silk or regenerated cellulose, or with highly twisted threads produced by other processes.

Where the fabrics contain threads of low twist or regenerated cellulose.

Fabrics containing highly twisted crepe threads prepared in accordance with the invention may be subjected to a hot aqueous treatment in the manner commonly adopted in connection with fabrics comprising highly twisted yarns of natural silk. A particular advantage of this invention is that creping baths of relatively low temperature, say 80 to 85 C., may be used whereby the delustering of the cellulose acetate yarn may, be avoided. However, if it is desired to decrease the time of treatment, creping baths of higher temperature up to'the boiling point may be used, in which case the delustering effect of the hot aqueous baths upon fabrics containing lustrous threads of cellulose acetate may be minimized by the addition-of salts or sugars to the baths.

In order to illustrate our invention, but not by way of limitation, the following examples are iven:

Example I Three pounds and five ounces of gelatin are stirred with twenty-nine pounds and eleven ounces of cold water. After standing at room temperature for 24 hours, the mixture is heated for one hour to 65-75 C. to complete the solution of the gelatin. The solution is cooled to 40 C. and thereupon' there are added 12.5 cc. of glycerine, 46 cc. of 40% formaldehyde and 231 cc. of a 10% aqueous solution of Brilliant Av'irol L-144WD (a sodium salt of sulfated higher fatty alcohol). This solution contains approximately 10% of solids.

Yarn of 166 denier comprising 40 filaments of acetone soluble cellulose acetate is'dipped in the form of hanks in the above solution'at 45 to 50 C., the hanks are then centrifuged down to about one and one-half times their original weight and dried in the air. This applies 5% of solids to the yarn. The hanks are then backwound onto bobbins. From these bobbins the yarn is twisted in the presence of steam to '70 turns per inch.

The so treated and twisted yarn is then woven as weft of 64 picks per inch into a fabric with a warp comprising 108 ends per inch of ordinary cellulose acetate, of 100 denier having 3 to 5 turns per inch, weft yarn of right-hand twist alternating with weft yarn of left-hand twist. The fabric is woven to a width of 45 inches. When this fabric is treated in a hot scouring creping bath good crepe effects are obtained. Thus a treatment for 15 minutes in a creping bath of 80-85 C. causes the original 45 inch wide fabric to shrink to a width of 33 to 34.5 inches, a treatment for 15 minutes in a creping bath of 98-100 C. causes shrinkage to 29-30 inches in width, while treatment for 2 hours in creping bath of 98-100 C. causes shrinkage to 28-29 inches in width.

Example II I cans. When this fabric is treated for 2 hours in a creping bath of 98 to 100 C., the fabric of an original width of 45 inches shrinks to a width of 27 inches.

Example III The cellulose acetate yarn of Example I is treated with an aqueous solution of the isolated protein derived from soya bean, the amount applied being 5% of the weight of the fabric. This .is crepe twisted in the presence of steam to 70 turns per inch and then woven into a fabric as -described in Example I. When the fabric of 45 tailed description is given merely by way of illustration and that many variations may be made therein without departing from the spirit of our invention.

Having described our invention, what we desire to secure by Letters Patent is:

1. Process for the production of crepe yarn of filaments of an organic derivative of cellulose, which comprises incorporating in the yarn a crepe promoting agent comprising a substance having a delayed solubility in water and crepe twisting the yarn while it is subjected to the action of a hot aqueous fluid.

2. Process for the production of crepe yarn of filaments of cellulose acetate, which comprises incorporating in the yarn a crepe promoting agent comprising a substance having a delayed solubility in water and crepe twisting the yarn while it is subjected to the action of a hot aqueous fluid.

3. Process for the production of crepe yarn of filaments of an organic derivative of cellulose,

' which comprises incorporating in the yarn a crepe promoting agent comprising a' protein and crepe twisting the yarn while it is subjected to the action of a hot aqueous fluid.

4. Process for the production of crepe yarn of filaments of cellulose acetate, which comprises incorporating in the yarn a crepe promoting agent comprising a protein and crepe twisting the yarn while it is subjected to the action of a hot aqueous fluid.

5. Process for the production of crepe yarn of filaments of an organic derivative of cellulose. which comprises incorporating in the yarn 9. formaldehyde treated protein and crepe twisting the yarn while it is subjected to the action of a',5

hot aqueous fluid.

6. Process for the production of crepe yarn oi filaments of cellulose acetate, which comprises incorporating in the yarn a formaldehyde treated protein and crepe twisting the yarn while it is 10.

subjected to the action of a hot aqueous fluid.

7. Process for the production of crepe yarnof filaments of cellulose acetate, which comprises incorporating gelatin in the yarn and crepe twisting the yarn while it is subjected to the action of a 15 hot aqueous fluid.

8. Process for the production 01' crepe yarn of filaments of cellulose acetate, which comprises incorporating formaldehyde treated gelatin in the yarn and crepe twisting the yarn while it is subjected to the action of a. hot aqueous fluid.

9. Process for the production of crepe yarn of filaments of an organic derivative of cellulose, which comprises incorporating in the yarn a protein derived from soya beans and crepe twisting the yarn while it is subjected to the action of a hot aqueous fluid.

10. Process for the production of crepe yarn of filaments of cellulose acetate, which comprises incorporating in the yarn a protein derived from soya beans and crepe twisting the yarn'while it is subjected to the action of a hot aqueous fluid.

11. Crepe yarns of filaments of cellulose acetate and having a protein derived from soya beans incorporated therein.

GEORGE SCHNEIDER. WILLIAM WHI'I'EHEAD. 

